Changelog:
===========
Make a retrocompatible version of 1.4.0 change about supporting VIXIECRON bug.
Added "implement_cron_bug" flag to make the cron parser compatible with a bug in Vixie/ISC Cron
Signed-off-by: Wang Mingyu <wangmy@fujitsu.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>